SPINAL CORD AND ROOT DISEASE

Dermatome of the umbilicus

T10

5 Motor Neuron Diseases in Adults

1) Progressive bulbar palsy - bulbar involvement, cranial nerves, LMN 2) Pseudobulbar palsy - bulbar involvement UMN 3) Progressive spinal muscle atrophy - LMN deficit in the limbs 4) Primary lateral sclerosis - UMN deficit in the limbs 5) Amyotrophic lateral sclerosis - UMN and LMN (includes PLS and PSMA)

Erb's palsy (which nerve roots?)

C5, C6 loss of shoulder abduction and elbow flexion Affected arm held internally rotated at the shoulder with pronated forearm and extended elbow. Biceps and brachioradialis jers are lost.

A 35-year-old woman falls 12 ft off of a ladder and fractures her c-spine, causing damage at the C4 level. She is initially a flaccid quadriplegic with areflexia. This areflexia and flaccidity usually evolve into hyperreflexia and spasticity within a. 2 to 4 months b. 1 to 2 months c. 3 days to 3 weeks d. 1 to 3 h e. 5 to 25 min

3 days to 3 weeks Spinal shock is a transient phenomenon that occurs with damage to fibers from upper motor neurons. The spasticity that usually develops within a few days of the spinal cord injury is presumed to represent exaggeration of the normal stretch reflexes in the limbs disconnected from upper motor neuron control. The evolution from spinal shock to spasticity is much more typical of spinal cord injuries than it is of cerebrocortical injuries, but even with cerebrocortical injuries there is usually an interval of hours to days during which limbs that eventually become hyperreflexic and spastic are hyporeflexic and flaccid.

The CSF analysis associated with spinal cord infarction may reveal a. An increase in the CSF gamma globulin content b. A depressed CSF glucose content c. A protein content of greater than 45 mg/dL d. More than 100 white blood cells (WBCs) per μL e. More than 100 red blood cells (RBCs) per μL

A protein content of greater than 45 mg/dL With spinal cord infarction, as with cerebral infarction, the CSF is relatively normal. If there is an abnormality, it is most likely to be an elevated CSF protein.

Bell Palsy

An example of mononeuropathy simplex. More common in diabetics and pregnant women. Facial weakness preceded by pain near ear. Treat with corticosteroids.

Posterior column syndrome would result in ...

Bilateral loss of proprioception below the lesion with relative preservation of pain and T sensation.

A 35-year-old man injured his thoracic spine 2 y ago. Initially he had a bilateral spastic paraparesis and urinary urgency, but this has improved. He still has pain and thermal sensation loss on part of his left body and proprioception loss in his right foot. There is still a paralysis of the right lower extremity as well. This patient has which spinal cord condition? a. Brown-Séquard (hemisection) syndrome b. Complete transection c. Posterior column syndrome d. Syringomyelic syndrome e. Tabetic syndrome

Brown Sequard Hemisection of the spinal cord - contralateral loss of pain and thermal sensation 2/2 spinothalamic damage, and ipsilateral loss of proprioception due to posterior column damage. Also ipsilateral motor paralysis due to destruction of the corticospinal and rubrospinal tracts.

twitching movements of chin preciptated by pursing of the lips

Bulbospinal neuropathy (Kennedy disease)

A 36-year-old man is being evaluated for left hand weakness. On examination, it is readily apparent the he has atrophy of the first dorsal interosseous muscle. This may indicate damage to spinal roots a. C5 and C6 b. C6 and C7 c. C7 and C8 d. C8 and T1 e. T1 and T2

C8 and T1 The first dorsal interosseous muscle is innervated by the ulnar nerve. The fibers of the ulnar nerve reaching this muscle originate at the C8 and T1 roots. If the ulnar nerve itself is the neural element injured, it is usually because of damage at the elbow, where the ulnar nerve runs superficially in the groove over the ulnar condyle. All the interosseous muscles of the hand are supplied by the ulnar nerve: complete transection of that nerve will produce interosseous wasting and impaired finger adduction and abduction. Although the lumbrical muscles are situated alongside the interosseous muscles of the hand, only two lumbricals— those on the ulnar metacarpals—are innervated by the ulnar nerve. The other two lumbricals are innervated by the median nerve. All four lumbricals insert on the extensor sheaths of the fingers and participate in extension of the digits.

Klumpke's paralysis (which nerve roots?)

C8, T1 Paralysis and wasting of small muscles of the hand and of the long finger flexors/extensors

Cervical rib syndrome

C8, T1 compressed by a cervical rib or band arising from the 7th cervical vertebrae. Leads to weakness and wasting of intrinsic hand muscles. Subclavian artery may be compressed thus Adson test can be used to diagnose i.e. radial pulse decreases in amplitude when the seated patient turns head to affected side and inhales deeply.

This type of lesion is most likely to evolve after neck trauma if there has been intraspinal: a. Hyperthermia b. Hypothermia c. Transient ischemia d. Contusion e. Demyelination

CONTUSION After cervical cord contusion, cyst formation may occur as damaged tissue is removed. This is especially likely if there has been extensive intraspinal hemorrhage. Ischemic damage may produce similar changes, but the ischemia must be substantial and persistent enough to produce infarction of spinal cord tissue. Demyelination does not lead to syringomyelia, even in cases with extensive intraspinal demyelination.

ALS

Can have cognitive alterations, dementia, *sensory and sphincteric functions are characteristically spared as well as autonomics and special senses*. CSF is normal.

Unvaccinated person with resp infection followed by palatal weakness, impaired pupillary responses

Diphtheritic polyneuritis

Lumbar veretbral body fractures are usually caused by flexion, extension, torsion, spondylolisthesis, or subluxation?

FLEXION Extreme flexion of the lumbar spine is likely in automobile accidents and in falls where the person is upright. Fracture of a lumbar vertebral body may be seen in vehicular accidents when the victim is restrained during a high-speed impact by a seat belt without a shoulder harness. The rapid and extreme forward flexion of the lumbar spine may produce a variety of spinal injuries, ranging from fractures to dislocations. Fractures suffered during falls in which the person is upright, such as may occur when someone jumps off a building, are usually compression fractures of the vertebral body. Fracture of the vertebral body will usually produce pain coincidental with the injury. Patients with fractures of the vertebral body that occur without trauma or with inconsequential trauma must be investigated for malignant processes, such as metastatic carcinoma, multiple myeloma, and unsuspected osteomyelitis.

70 yo man with pain at level of umbilicus and leg weakness/pain when walking

ISCHEMIC SPINAL CORD DISEASE The aorta is the principal source of blood for the spinal cord. Vessels that supply the cord are somewhat variable in their origins, but they most commonly arise as branches of the vertebral and hypogastric arteries, as well as of the aorta at the level of the upper and lower thoracic vertebrae. The artery most implicated in a patient with this constellation of complaints is the great anterior medullary artery (of Adamkiewicz), which arises from the aorta at the level of T10-L1 and supplies the anterior median spinal artery (lower limbs + bladder/bowel control affected)

Treatment of ALS

Riluzole (anti NMDA R) prolonged survival by 2-3 mo Symptomatic treatment incl muscarinic antocholinergic drugs if drooling, saliva is troublesome ex glycopyrrolate, trihexyphenidyl, amitryptilline)

Slipped disk

L5-S1 L5 radiculopathy = weakness of dorsiflexion of foot, toes S1 radiculopathy = weakness of plantar flexion of the foot/ depressed ankle jerk

Winging of the scapula

Long thoracic nerve (C5,6,7), weakness of serratus anterior.

The posterior column neurons decussate at what level? a. At the medulla b. At the midbrain c. At the pons d. At the thalamus e. Within one or two levels after entering the spinal cord

MEDULLA After the primary sensory fiber enters the spinal cord, the ascending branch enters the dorsal columns and travels to the medulla. The fibers from the legs and trunk travel medially in the fasciculus gracilis, while those from the arm and neck travel laterally in the fasciculus cuneatus. These first-order neurons synapse in the medulla, and then the second-order neurons decussate as the internal arcuate fibers and ascend in the medial lemniscus. The second-order fibers synapse in the ventroposterolateral (VPL) nucleus of the thalamus, which then synapses on the somatosensory cortex.

A 57-year-old woman began having weakness and trouble walking 1 year ago. Current exam findings include weak, wasted muscles with spasticity, fasciculations, extensor plantar responses, and hyperreflexia. This is most suggestive of a. Dorsal spinal root disease b. Ventral spinal root disease c. Arcuate fasciculus damage d. Motor neuron disease e. Purkinje cell damage

MOTOR NEURON DISEASE Motor neuron disease in the anterior horns of the spinal cord and damage to the corticospinal tracts or motor neurons contributing axons to the corticospinal tracts would account for these neurologic signs. Damage to the ventral spinal roots would produce weakness and wasting, but no spasticity or hyperreflexia would develop. Purkinje cell damage would be expected to produce ataxia without substantial weakness.

A 19-year-old man goes swimming in an inland pond in Puerto Rico. Several wks he develops lancinating pains extending down his legs and all of his toes. Over the course of just a few days, he develops paraparesis and problems with bladder and bowel control. Within 1 week, he is unable to stand and has severe urinary retention. 438. The most appropriate plan of action on an emergency basis is to a. Initiate anticoagulation b. Perform sensory-evoked potential testing c. Order an MRI scan d. Place a cervical collar e. Perform spinal angiography

ORDER AN MRI MRI scanning is the best emergent test when available, as it will show compressive lesions as well as processes, such as tumors, inflammation, or infection, which may affect the parenchyma of the spinal cord itself. Vascular lesions, such as spinal cord AVMs, may also be seen on MRI, although spinal angiography is often required to confirm the lesion and guide therapy.

Rapid progressive acute peripherla neuropathy with sensory symptoms and a rapidly ascending paralysis beginning 30 minutes after eating affected shellfish.

Paralytic shellfish poisoning (SAXITOTOXIN)

Infective anterior horn cell disorders

Poliomyelitis - Symmetric LMN weakness after fever, myalgia, malaise. Isolate virus from stool or naropharyngeal secretions. Often useful recovery occurs. West Nile - meningoencephalitis/paralytic poliomyelitis

Colicky abdominal pain, sometimes also felt in back or thighs, followed by symmetric weaknes. What is this and how to treat it?

Poryphyria: The acute, or hepatic, porphyrias primarily affect the nervous system, resulting in abdominal pain, vomiting, acute neuropathy, muscle weakness, seizures and mental disturbances, including hallucinations, depression, anxiety and paranoia. Cardiac arrhythmias and tachycardia (high heart rate) may develop as the autonomic nervous system is affected. Pain can be severe and can, in some cases, be both acute and chronic in nature. Constipation is frequently present, as the nervous system of the gut is affected, but diarrhea can also occur. Diagnose with increased levels porphobilinogen or gamma-aminolevulinic acid in the urine *Treat with dextrose to suppress the heme biosynthetic pathway and propranolol to control tachy and HTN. Best index of progress is HR.*

Lasegue sign

Restricted straight leg raise in disk prolapse due to reflex spasm of hamstring muscles

Syringomyelic syndrome

Results from a lesion of the central gray matter (usually with syringomyelia which is when a cyst or cavity forms within the spinal cord). It can expand over time destroying spinal cord. Pain and temperature fibers that cross at the anterior commissure are affected, which may result in bilateral loss of these sensations over several dermatomes. However, tactile sensation is spared. Syringomyelia may also cause a loss of the ability to feel extremes of hot or cold, especially in the hands. Trauma, hemorrhage, or tumors are other possible etiologies. If the lesion becomes large enough, then other spinal cord systems become affected as well.

A biopsy of the spinal cord shows widespread granulomas at the level of the patchy irregularity seen on MRI. In the midst of one granuloma is an ovoid mass with a spine extending from one side. The pathologist interprets this as a parasitic ovum. If the pathologist is correct, the most likely cause of the lesion is

SCHISTO MANSONIA Schisto can cause ovums in the granuloma of spinal cord. Note: T. (taenia) pallidum may produce a granulomatous lesion in the spinal cord (gumma) but not an ovum *Treat with praziquantel*

2 mo infant floppy, difficulty with suckling, swallowing, breathing

SMA1 (Werdnig Hoffman disease) Usually die from resp issues by age 3 Autosomal recessive

8 mo infant with wasting and weakness of the extremities, slowly progressive

SMA2 i.e. Chronic Werdnig Hoffman disease Many pts survive into adulthood. Treatment is supportive

Which of the following would you expect to find in this patient 6 months from now? a. Fasciculations b. Fibrillations c. Flaccid paralysis d. Hyporeflexia e. Spastic paralysis

SPASTIC PARALYSIS This patient has an upper motor neuron lesion. The damage has been done proximal to the synapse of the anterior horn of the spinal cord. He will therefore develop a spastic paralysis. Fasciculations, fibrillations, flaccid paralysis, and hyporeflexia are all found following lower motor neuron lesions (at the anterior horn cell or more distally).

61 yo man who smokes and and has HTN, 8 hours of abd aortic aneurysm repair, is unable to move his legs and says they are numb. He has a flaccid paresis of both lower extremities and impaired pinprick sensation at T9 bilaterally. Normal joint proprioception.

SPINAL CORD INFARCT Probably 2/2 anterior spinal artery occlusion.

Syrinx

Sausage shaped structure in the spinal canal. That this patient has syringomyelia independent of neoplasia, infarction, or intraspinal hemorrhage is suggested by the protrusion of cerebellar structures below the foramen magnum. The combination of a low-lying vermis or cerebellar tonsils and syringomyelia points to a Chiari malformation. Syrinxes usually result from lesions that partially obstruct CSF flow. At least ½ of syrinxes occur in patients with herniation of cerebellar tissue into the spinal canal, called Chiari malformation), brain (e.g. encephalocele), or spinal cord (e.g. myelomeningocele) Can also develop in patients who have a spinal cord tumor, scarring due to previous spinal trauma, or no known predisposing factors. About 30% of people with a spinal cord tumor eventually develop a syrinx.

Acute foot drop during labor

Short women, due to compression of lumbosacral trunk by fetal head at pelvic brim. Complete recovery within 6 mo.

Tabetic syndrome

Tabetic syndrome results from damage to proprioceptive and other dorsal root fibers. It is classically caused by syphilis. Symptoms include paresthesias, pain, and abnormalities of gait. Vibration sense is most affected.

The arteria radicularis magna (artery of Adamkiewicz) enters at approximately what level? a. C2-C5 b. C5-C8 c. T2-T8 d. T10-L1 e. L4-S4

The artery of Adamkiewicz is a major anterior radicular artery and may supply the lower two-thirds of the spinal cord. It is at risk of occlusion during abdominal aortic aneurysm repair. Other branches off of the aorta or internal iliac arteries may also supply the thoracic and lumbar cord. The upper segments of the spinal cord are usually supplied off the vertebral arteries.

The lateral corticospinal tract decussates at what level? a. At the junction of the medulla and the spinal cord b. At the junction of the midbrain and the medulla c. At the junction of the pons and the medulla d. At the thalamus e. Within one or two levels after entering the spinal cord

The lateral corticospinal tract originates primarily in the precentral gyrus (primary motor cortex). These axons then travel in the posterior limb of the internal capsule, and then the middle section of the cerebral peduncle. They enter the basal pons and continue as the pyramids in the medulla. At the decussation of the pyramids, the lateral corticospinal tract crosses and then continues down the spinal cord.

In Brown Sequard, where would you expect the pain and temperature abnormalities to begin? a. Exactly at the level of the lesion b. Four or five segments above the lesion c. Four or five segments below the lesion d. One or two segments above the lesion e. One or two segments below the lesion

The spinothalamic system is responsible for pain and temperature sensation. It enters the spinal cord through the dorsal root ganglion. The second-order neurons then ascend one or two levels as they cross in the anterior gray commissure. Thus a lesion of the right spinothalamic tract at the T8 spinal cord level would result in a contralateral loss of pain and temperature on the left body beginning at approximately the T9-10 dermatome.

Diagnosing ALS

Upper and lower motor neuron signs in the bulbar and 2 spinal regions or in three spinal regions (cervical, thoracic, lumbosacral)

Which modality of sensation is usually spared with spinal cord ischemia?

VIBRATION. Spinal cord ischemia is usually most severe in the distribution of the anterior spinal artery. The posterior spinal artery is more a plexus of arteries with extensive anastomoses than a discrete pair of blood vessels running along the dorsal aspect of the spinal cord. With a lesion of the spinal cord from ischemia or pressure, the spinothalamic tracts, which are responsible for pain and temperature perception and for providing information for two-point discrimination and graphesthesia, are more vulnerable to injury than are the posterior columns. The posterior columns, which are primarily responsible for vibration and position sense, are supplied by the posterior spinal arteries.

Slight increase in CSF protein, and an MRI of the lumbar cord with gadolinium reveals patchy enhancement at about the L4-L5 spinal cord level. These findings suggest ...

With a transverse myelitis, inflammation is largely limited to the substance of the cord and there need not be an apparent mass effect. This type of reaction may occur with a variety of noninfectious processes, such as MS and sarcoid, or infectious processes, such as viral and parasitic infections.

Spinal claudication

With exertion, blood that would be available to the spinal cord under resting conditions might be shunted to the more patent blood vessels of the limb muscles. Unlike more typical claudication, in which leg pains develop because of poor blood flow to leg muscles, the leg pains of spinal claudication develop because of *shunting of blood to the leg muscles*. The pain is a reflection of ischemia to the sensory neurons in the spinal cord. pondylolysis (the idiopathic dissolution of vertebral elements) may lead to pain with exertion because of the vertebral instability associated with these commonly linked conditions. Myotonia and myokymia are disturbances of muscle activity that would not be expected in association with ischemic spinal cord disease

Parsonage-Turner syndrome

aka brachial plexopathy- neuralgia amyotrophy severe shoulder pain followed a few days later by weakness, reflex changes, sensory disturbances. Usually unilateral. Wasting of affected muscles is profound.

ALS prognosis

fatal within 3-5 years (pulm infection)

Peripheral nerve disorders usually start with

sensory symptoms and signs

Spondylolysis

the idiopathic dissolution of vertebral elements may lead to pain with exertion because of the vertebral instability associated with these commonly linked conditions

Spondylolisthesis

the slippage of vertebral elements, most often after trauma. Forward displacement of a vertebra, especially L5, most commonly occurring after a break or fracture. May lead to pain with exertion because of the vertebral instability associated with these commonly linked conditions